Improvement in rotary valves



2 Sheets-Sheet 1.

D. JOB. Rotary-Valve.

Patented Nov. 13, 1877. Z.

(NV NTOR @anni n1 mqqdi '-'f NV PETERS. PHOYO-Ll 2 Sheets-Sheet; 2.

D. JOB.

i Rotary-Valve.

Patented Nov. 13, 1877. 4Z

OMAL

N. PETERS. PHDTOUTHUGRAPHER. WASHINGTON, D C.

` UNITED STATES PATENT OFFICE..

DANIEL JOB, OF NILES, OHIO.

j IMPROVEMENT IN RoTARY VALVES.

i y Speciicationforming part of Letters Patent No. 191,139, dated November 13, 1877; application iled September 15, 1877.

itains to make and use it, reference being had to the accompanying drawings, which form part of' this speciiication.

' My invention relates to steam-engines; and consists in novel mechanism whereby steam is supplied to, and exhausted from, the steam'- cylinder, and`whereby the direction of motion of the engine can be quickly reversed.

In the drawing, Figure l represents a device embodying my invention. Fig.'2 represents a top and bottom view of the conduit-chamber, showing steam passages and openings. Fig. 3 is a side view of the conduit-chamber. Fig. 4 represents a cross-section of the throt- 't-le-valve and its casing. Fig. 5 shows a bottom view of the throttle-valve. Fig. 6 represents a top and end view of the steam-cylinder and its slide-valve and steam-passages. Figs. 7, 8, and 9 represent the throttle-valve in three different positions relative to the'top openings of the conduit-chamber.

A is the throttle-valve, having a hollow rod or stem, B, firmly attached to it. b is a handle secured to said rod or stem, by which the positionof the throttle-valveAcanbe changed.

C is a casing, in which the valve and part of valve-stem are contained. It is rmly attached to the top of the conduit-chamber, over the central part of the same.

The valve A is provided with an opening, a, and with.a passage, al. The former communicates with the inlet-aperture a2, through which steam enters on its way to operate the pistons, while the latter communicates with the hollow throttle-valve rod B, which serves as a conduit for the exhaust steam.

The valve A is also provided with the depressions as, which communicate with the passage al, the purpose of which is to allow the steam to escape or exhaust from the pistoncylinders when the supply of steam is entirely cut off. i

The valve A iits over a small projection, d,

of the conduit-chamber, which serves to hold the valve in a central position. A small space, c, is left between the top of the valve A and the roof of the surrounding casing, so that the entering steam may always pass through the 'opening a, no matter where said opening may be shifted to when the position of. the valve is changed.

D is the conduit-chamber, provided with the steam-passages d1 and d2. The passage d1 communicates, in its central part, with the upper aperture d5, and at its extremities with the lower apertures d3. The passage d2 commnnicates, in like manner, with the upper aperture d6 and the lower aperturesd` This conduit-chamber D is connected with the steam-cylinders of, preferably, two pistoncylinders by placing the openings d3 d* of chamber D over openings Z7 d of the steamcylinders, (see Fig. 6,) though it is equally applicable to a single cylinder.

The steam-cylinders E are provided with a steam-passage, f, in addition to the passage -g. The former communicates with opening d8, the latter with d'1.

The passage f communicates at each end with the valve-passage gby means of the passages L h', Fig. 6. The slide-valve L, moving in the passage g, is provided with two heads, m m', at each end of a connecting-rod. p and p are two ports, which connect the passage g with the piston-cylinder in which moves the piston P. -v

The conduitchamber may be so constructed as to communicate with more than two pistoncylinders, as is evident, and no interference will result.

The operation of the device is as follows: When the throttle-valve A is in the position shown in Fig. 7, the steam that enters through passage a2 passes through openings a and d6 into the conduit-chamber, from which itpasses, by way of d* and d", into the steam-passage f, as indicated by the arrow. When,now, the slide-valve is in the position shown in Fig. 6, the steam that enters through d. will take the direction indicated by the arrows, passing from passage f to passage h' through port p7 of cylinder g into the piston-cylinder, driving the piston in the direction of the arrow. The steam in front of the piston passes from the piston-cylinder into passage g by way of port p, and then out of passage g by way of opening d", into the conduit-chamber through opening d3. It then passes from the steam-passage d1,through the upper opening d5, through the passage al of the throttle-valve, into the hollow stem of the same, from whence it is exhausted.

When, now, it is desired to reverse the engine, the operator takes hold of the handle b and gives the throttle-valve a half-revolution, so that it will be in the position shown in Fig. 9. The course of the entering steam is, in that case, as follows: Through passage a2, opening a and d5, passage d, opening d3, and port d?.

Assuming the steam-piston P to be in the position indicated by Fig. 6, and also moving in the direction shown by the arrow, then the moment the throttle-valve is given the halfrevolution referred to, port d1 ceases to be an exhaust-port, and becomes the steam-port. The steam that enters through it passes into the steam-cylinder through the port p, arrests the motion of the piston, and moves it in the opposite direction, thus reversing the movement of the engine. Steam is now exhausted through port pl, passage h', passage f, port d", opening di, passage dl, upper opening d6, and passage al, to the hollow throttle-valve rod B.

When it is desired to cut off the supply of steam, the operator moves handle b sucient to give the throttle-valve a quarter-revolution from either of the before-mentioned positions, as indicated in Fig. 8. As neither of the openings in the conduit-chamber is now opposite the opening a of the valve no steam can, of course, enter. The depressions or passages a3, however, are so placed as to overlap, to a greater or less extent, the openings d5 and d6 when the throttle-valve is in the position shown in Fig. 8, so as to allow steamto be exhausted from both ends of the pistoncylinder at the same time.

The slide-valve L is operated by suitable connections with the steam-piston rod or other parts of the engine, in any usual well-known manner.

It is evident from the foregoing description that the engine can be almost instantly reversed, as it takes but an instant to shift the position of the throttle-valve.

It will also be observed that by my invention the throttle-valve serves the four functions of admitting, cutting off, reversing the direction of, and exhausting, the steam.

This-device is found to operate very satisfactorily in practice. The engine can be reversed almost instantly; all link mechanism is dispensed with; and the operation of one, two, or any number of engines may be controlled instantly by simply an .operation of the throttle-valve alone.

What I claim is- The combination, with steam-ports d5 d6, of the rotary valve, provided with a hollow stem and passages a3 leading to the exhaust-passage a and steam-passage a, whereby both ends of the cylinder may be open to the exhaust when steam is cut olf, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

DANIEL JOB.

Witnesses F. ToUMEY, v WM. E. DONNELLY. 

